Mechanical pencil



May 17,1927.

B. AVAKIAN MECHANICAL PENCIL Filed JuneB. 192.6.

5555.721.3333 uuuwwnnvninuuliws i the pencil;

' Patented May 17, 1927.

BYAGDASAB A VAVXIA, O F ARLINGTON, RHODE ISLAND.

MEQHANIGAL rauen..

Application filed June 8, 1926. Serial No. 114,463.

ments in t ev process of manufacture and disassemblin them for repair.

Another o ject of the invention is to provide a pencil of the type specified from which worn or broken parts may be easily removed and replaced without mutilating or destroying the main body or barrel of the pencil.

Another object ofthe invention is to pro;` vide a pencil of the type specified having a propelling and retracting unit which may be assembled with holders or barrels of different lengths .and which is also adapted for use with holders having interior bores' which vary slightly in size. j

Further objects and advantages of the improvement are set forth in the V'following specication which describes a preferred form of construction of the invention as illustrated by the accompanying'drawings.

In the drawings: Y

Fig. 1 is a side View of the pencil showing its body or casing in section and illustrating the relative locationof its several parts Fig. 2 is a longitudinal sectional view...of

Fig. 3, is a cross-'seeth nal view of the pen cil taken on line 3f-3 o Fig. 2;,and

Fig. 4 is a cross-sectional view taken on line 4--4 of Fig. 2.

It is the usual practice inthe manufacture of mechanical pencils to provide a unitary lead propelling andv retracting means whichma y be conveniently assembled withinl the main sleeve'or tube forming the body or barrel ofthe pencil.' The body or barrel of the pencil-is usually constructed from a sleeve or tube 0f vulcanized rubber or composition, which may be of different sizes and lengths. Prior to the present invention the j lead propelling and retracting unit hasigenf `erally been assembled with the tubular barrel of the pencil by forcingthe unit into the interior bore thereof. .It has been found,

howev r, that this methodof .assembling the r. pencill las many disadvantages; for instance, where the propelling unit 1s made to fit duced in diameter at be loosely held in others which have a slightly larger bore; and again, when made to fit'a barrel of the maximum bore and assembled with a holder of smaller bore the forcing of the unit into the barrel will split or crack the material of the holder. Pencils of the present type frequently become inoperative, due to derangement of the parts or clogging of the leads, and it is then necessary for repair and replacement. This often re sults in thebreaking of the tubular holder or barrel of the pencil where the propelling unit is forced into a tight-fitting sleeve. To obvlate these disadvantages the present invention provides an improved means for securing the lead propelling and retracting unit in place in tubular holders or pencil,- barrels having'b'ores of varying sizes, and

also facilitates the easy disassembling and re-assembling of the parts of the pencil when repairs are necessary. A

Referring to the drawings, .theouter shell or barrel 2 constitutes pencil, and usually an eraser 3is inserted in the upper end of its bore and the barrel refor covering the eraser. The operating unit the main body of the` 5 to receive a cap 6 to disassemble the operating elements 7 which constitutes the lead propelling and retracting means is receivedl in a conical' nlozzle 8l fitted over-thereduced lower end of t ie opening 9 through which the Writing lead l() is projected. A bushing 11 is soldered or brazed within the throat ofthe nozzle 8, and secured fast thereto is an inner "tubular sleeve 12 provided with a longitudinal slot 13 in its side. A helically-wound tube 14 is rotatively mounted on the sleeve 12 and heldfrom longitudinal displacement with respect thereto by splitting the upper end of thel sleeve and swagingv it outwardly to form ears 15, s'eeI Fig. 4, lwhich project across the top of the tube 1li. v j' The writing lead 10 is held in an inner tubular carrier 16 slidably mounted in the sleeve 12 and adapted to be adjusted'therealong by' means of a pin 17 projecting from) the carrier. into the slot 18 of the helical 4propelling sleeve 14. An expelling rod 19 is s'lidably mounted in the carrier 16 with its bent end 20 projecting through a slot 21 in the carrier 16 and through. the slot 13 in the sleeve 12. The end 20 of the rod 19 older 2 and terminating in acontracted projects into the helical slot 18 of the tube 14 directlyabove the. pin 17 on the lcarrier 16, see Fig. 2.

n of the barrel 2 by an improved construction as later described. The construction of the lead propelling and retracting means above described is in: accordance with the usual arrangement so that further description thereof is unnecessary. Suiice'it to 'state that the pencil lead ispropelled in the usual mannerby turning'the holder or barrel 2 ofthe vpencil with respect to its lowernozzle-portion 8 carrying the bushing -11 and inner tube 12. lThe helical operating sleeve 14 will thus be turned with the barrel 2 and the pins 1f? and 20 engage with the groove 18 ofv the sleeve14 to slide' the carrier 16 and rod 19 tofproject the vlead 10 out through the reduced opening in the nozzle 8 or to retract it therei'nto.

As before noted, the present invention consists ina novel and improved means for' securing the helical sleeve or operating vscrew 14 fast within the barrel 2. lThe ltube 22 connected withv the screwl 14 is slotted on opposite sides at its lupper end as indicated by the reference numeral 23 in Figs. 1 and 3, and its interior is threaded rto receive a tapered screw or expanding plug 24.A The propelling unit 7 is assembled with the body portion or barrel 2 of the pencil by sliding the sleeve 22 into the bore thereof until the upper end of the conical nozzle 8 seats against the shoulder 25 at the lower end of the barrel. The screw 24 is then turned down into the interiorly-threaded tube 2 until its clutch/-like jaws formed by the sli s 28are expanded to grip the interior of`the barrel 2. It is to be noted that the sleeve 22 is preferably knurled or roughened on its exterior to provide a secure .grip in the interior bore of the holder 2. Y"

As illustrated in the accompanying draw- .f ings, see Figs. 1 and 2, the lead propelling and retracting unit 7 extends substantially midway of the. length of the barrel 2, the remaining space in the barrel between the top of the screw 24 and the eraser 3 serving as a magazine for holding a supply of extra lleads 10. c

' It will be observed that my improved construction provides for the easy assembling of the lead propelling and retracting unit within the tubular barrel ofthe pencilv without danger of splitting or breaking/the barrel.

1 The. only operation necessary is to tighten the tapered expanding plug-24 at the top ofthe unit so that no fitting or ,forcing of the parts is required. It will'also be observed that should any of the parts of the unit become disarranged or the leads clogged therein, or the operating mechanism become broken or otherwise damaged, the propellinr and retracting unit may be readily removed from the barrel of the pencil by loosening the adjusting screw 24 without danger of mutilatinof or damaging the main parts of the penci Moreover, the invention provides means for assembling thepropelling and retracting unit with vtubular holders 0r pencil barrels of different lengths and slightly varying bores whereby to facilitate theprocess of manufacture, and further to render the pencil more convenient to repair.

IVhile I have herein illustrated and described a preferred embodiment of my improved device it is obvious that various modiiications may be made in the structure and arrangement of its parts without departing from the spirit and scope of the invention. Therefore, without limiting myself in this respect, I claim:

1 1. In a mechanical pencil, the combination with the barrel thereof, of a tubular member within said barrel, and means for expanding said tubular member to adapt it to grip the'interlor walls of the barrel to secure it rotatively therewith.

2. In a mechanical pencil, the combination with the barrel tiereof, of lead propelling and retracting meansL comprising a screw member, a threaded bore at the endl of said screw member, and an expansion screw engaging saidbore to adapt it to expand the screw member`to cause it to securely grip the interior of the bore in the barrel.-

. 3. In a mechanical lead pencil. the combination with the barrel thereof, of lead propelling and retracting means contained within the barrel,.said means comprising a screw member having a threaded bore at its end with longitudinal slits on its sides, and a tapered plug adapted to bescrewed into sai'd bore to expand the sides of the memberto adapt them to grip the interior of the barrel.

4. Ina mechanical pencil, the combina-i 'sleeve at the end of said screw provided with a roughened exterior and longitudinal slits 1n its sides, and a tapered screw adJustable Within the sleeve to expand its sides tol cause them to grip the interior of the barrel. In testimony whereof I aiix my signature.

' BAGDASAR AVAKIAN. 

